1. Department of Biochemistry, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa
2. Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa
3. Department of Horticultural Science, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa
4. Department of Chemistry, Central Analytical Facility (NMR Unit), Stellenbosch University, Matieland, 7602 Stellenbosch, South Africa
5. University of Natural Resources and Life Sciences (BOKU), Department of Chemistry, Institute of Analytical Chemistry, 1180 Vienna, Austria
6. Central Analytical Facility, Stellenbosch University, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa